Movable base with control surface

ABSTRACT

In a further embodiment, a method of controlling a base assembly can be provided. An actuation member can be pumped to deploy one or more wheels to lift a base assembly on said wheels. Further, a pin can be received in a holding portion on a semi-planar contoured surface in response to the pumping of the actuation member. The wheels can be held in a deployed position via the pin being held in the holding portion. Further pumping of the actuation member can separate the pin from the holding portion and retract the wheels from the deployed position.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the priority benefit under 35 U.S.C. §119(e) toU.S. Provisional Patent Application Ser. No. 61/361,320 (filed 2 Jul.2010), the entirety of which is hereby expressly incorporated byreference herein.

BACKGROUND OF THE INVENTIONS

1. Field of the Inventions

The inventions generally relate to load-supporting bases, and moreparticularly load-supporting bases with retractable wheels.

2. Description of the Related Art

In some cases heavy objects such as ladders and platforms are desired tobe portable to enable their use in a variety of locations. For example,it is a common practice at retail stores to keep inventory in highshelves above the merchandise accessible to customers. The inventory isaccessed using a portable ladder device that has wheels enabling theladder to move about the store. A break device is sometimes providedwith these ladders to immobilize the ladder when being used to accessthe inventory.

Other heavy objects are enabled to move or be immobilized by specializedmechanisms. For example, U.S. Pat. App. Pub. No. 2005/0189005 disclosesa wheel lifted from the ground by a foot that is raised and lowered byturning a small screw in clockwise and counter-clockwise directions.Although this allows the apparatus to move on and off of the wheels, themechanism provided may be inconvenient as the rotation of the screw maybe difficult when the apparatus bears a heavy load.

SUMMARY OF THE INVENTIONS

One aspect of the inventions is to provide a movable base that is easyto move between configurations where the wheels are either deployed orretracted. For example, in one embodiment a base assembly can include aload-bearing base. The load-bearing base can have one or moredownward-facing recesses. Additionally, one or more wheels can berotatably mounted within the load-bearing base. The wheels can bemovable between a first wheel position within the one or moredownward-facing recesses and a second wheel position extending out ofthe one or more downward-facing recesses. An actuating member can alsobe movably coupled to the base. Then, a transmission rod can be coupledto the actuating member such that actuation of the actuating membercauses the transmission rod to translate relative to the load-bearingbase. Further, a pin can be mounted to the transmission rod. A pin pathcan be substantially defined by a contoured surface on a control platerotatably mounted to the load-bearing base. The pin can move from afirst stable position and enter into a second stable position along thepath upon a first actuation of the actuating member. The pin can exitthe second stable position and return to the first stable position alongthe path upon a second actuation of the actuating member. The motion ofthe transmission rod can cause the pin to move between the first andsecond plate positions and the wheels to simultaneously move between thefirst and second wheel positions.

Another embodiment of the invention can include a base assembly having aload-bearing base. An actuating lever can be movably coupled to thebase. A transmission member can operatively couple to the actuatinglever. A pumping of the actuating lever can cause the transmissionmember to move relative to the load-bearing base. A pin can be mountedto one of the transmission member and the load-bearing base. The pin canthen move in at least one direction relative to the transmission memberor load-bearing base. Further, a control element can be mounted to theother of the transmission member and load-bearing base. The controlelement can then also move in at least one direction relative to thetransmission member or load-bearing base. The control element can have asurface defining at least one stable holding position for the pin. Thepin can be received in the stable holding position upon a first pump ofthe actuating lever and can be separated from the stable holdingposition upon a second pump of the actuating lever. A plurality ofwheels can be rotatably mounted to the load-bearing base. The wheels canbe movable between a first wheel position not supporting the base and asecond position where the wheels can support the base. Movement of thewheels between these positions can correspond with the movement of thepin relative to the control element.

In an additional embodiment, a control mechanism can include a pindisposed on a housing. A control element can also be disposed on thehousing. The control element can be disposed on the housing such thatthe control plate can at least move relative to the pin. The controlelement can also define a surface comprising an angled portion, aholding portion, and an offset portion. A first motion of the controlelement relative to the pin can cause the pin to traverse the angledportion. A second motion of the control element relative to the pingenerally opposite the first motion can cause the holding portion toreceive the pin. A third motion of the control element relative to thepin generally in the same direction as the first motion can cause thepin to be separated from the holding portion and to traverse the offsetportion. A fourth motion of the control element relative to the pingenerally in the same direction as the second motion can cause the pinto be separated from the offset portion.

In a further embodiment, a method of controlling a base assembly can beprovided. An actuation member can be pumped to deploy one or more wheelsto lift a base assembly on said wheels. Further, a pin can be receivedin a holding portion on a semi-planar contoured surface in response tothe pumping of the actuation member. The wheels can be held in adeployed position via the pin being held in the holding portion. Furtherpumping of the actuation member can separate the pin from the holdingportion and retract the wheels from the deployed position.

BRIEF DESCRIPTION OF THE DRAWINGS

Some preferred embodiments of the inventions will now be moreparticularly described by reference to the accompanying drawings inwhich:

FIG. 1A is a side view of one embodiment of a movable base supporting anumbrella;

FIG. 1B is a side view of the movable base of FIG. 1A wherein wheels aredeployed;

FIG. 2A is a perspective view of the base of FIG. 1A with the coverremoved;

FIG. 2B is a perspective view of the base with wheels deployed, as inFIG. 1B with the cover removed;

FIG. 3A is a side view of the base in the configuration depicted in FIG.2A, with the interior of the frame shown in phantom;

FIG. 3B is a side view of the base in the configuration depicted in FIG.2B, with the interior of the frame shown in phantom;

FIG. 3C is an enlarged side view of the base of FIG. 3B at 3C-3C;

FIG. 4A is a perspective view of the interior of the frame of the baseof FIGS. 2A, 2B in a first position;

FIG. 4B is a perspective view of the interior of the frame of the baseof FIGS. 2A, 2B in a second position;

FIG. 4C is a perspective view of the interior of the frame of the baseof FIGS. 2A, 2B in a third position;

FIG. 4D is a perspective view of the interior of the frame of the baseof FIGS. 2A, 2B in a fourth position;

FIG. 4E is a perspective view of the interior of the frame of the baseof FIGS. 2A, 2B in a fifth position;

FIG. 4F is a perspective view of the interior of the frame of the baseof FIGS. 2A, 2B in a sixth position;

FIG. 5 is a perspective view of the locking plate of FIGS. 4A-4E;

FIG. 5A is a perspective view of the locking plate of FIG. 5 indicatinga path between the positions of FIGS. 4A-4F; and

FIG. 6 is a cross-sectional view of the base of FIG. 4A at 6-6.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

FIGS. 1A and 2A depict an x-y-z Cartesian coordinate system, with thebase assembly 10 primarily lying in the x-y plane. To assist in thedescription of these components, the following terms are used. Asdescribed herein, terms such as “height” refer to distance in thez-direction, and “higher/upward” and “lower/downward” refer to thepositive and negative z-direction, respectively. Similarly, terms suchas “lateral” will refer to the y-direction and “longitudinal” will referto the x-direction. However, in other embodiments these axes could berotated, reversed, or otherwise altered. A detailed description ofpreferred embodiments of movable base assemblies and their associatedmethods of use now follows.

FIG. 1A illustrates one embodiment, in which an umbrella system 1 caninclude an umbrella mounted on a movable base assembly 10. As depicted,the umbrella includes an umbrella canopy 4 and a single umbrella pole 8.However, in other embodiments the umbrella system 1 can have differentforms, such as including a cantilevered umbrella. Further, in otherembodiments another item to be supported by the base assembly 10 can besubstituted for the umbrella, such as a space heater, street lamp,general purpose cart, semi-mobile furniture such as a desk or chair, orthe like. The umbrella pole 8, or other items, can mount to a mountingportion 12 on the base assembly 10.

As further depicted in FIG. 1B, the base assembly 10 comprises aplurality of wheels 22. Thus, the base assembly 10, and the umbrella (oranother load) can be easily rolled to different locations on the wheels22, when deployed. Comparing FIGS. 1A and 1B shows that the wheels 22can also be retracted.

FIGS. 1A and 1B also depict an actuating member 58, depicted as a leveror foot pedal. As will be discussed further below, the wheels 22 of theumbrella system 1 can be retracted upon actuation of the foot pedal 58.The wheels 22 can be retracted into a cover 14, and the cover can thensubstantially bear the weight of the umbrella or other load. When thewheels 22 are retracted, the bottom surface of the cover 14 can producesufficient friction with the ground to substantially hinder sliding orother lateral movement of the umbrella system 1. Thus, in someembodiments the umbrella assembly 1 can stay in a desired position whenthe wheels are retracted.

It will be noted that, in the depicted embodiment, the wheels 22 cancontinue to contact the ground on which the base assembly 10 (and thecover 14) rest even when the wheels 22 are in a retracted position, aswill be explained further below. Nevertheless, the wheels 22 can bare arelatively small portion of the weight of the umbrella system 1 incomparison to the cover 14. Thus, ever though the wheels 22 can contactthe ground, the cover 14 can still substantially prevent sliding orrolling of the umbrella system 1. However, in other embodiments thewheels 22 can be configured to not touch the ground when in a retractedposition.

FIGS. 2A and 2B depict the base assembly 10 without the cover 14. Thecover 14, when present as in FIG. 1B, can rest on the remainder of thebase assembly 10, such as on the frame 18 depicted in FIGS. 2A and 2B.Thus, the deployed wheels 22 can support the frame 18, the frame 18 cansupport the cover 14, and the cover 14 can support a load, such as anumbrella. When the cover 14 is present, as depicted in FIG. 1A, thewheels 22 can be withdrawn or retracted into one or more downward facingrecess defined by the cover. The cover 14 can then, as discussed above,be in direct contact with and be supported by the ground. The wheels 22can thus be suspended above the ground by the cover 14, or alternativelybear a relatively small portion of the weight of the umbrella system 1.

The cover 14 is depicted as completely covering the frame 18 and otherparts of the base assembly 10, but the cover can also take other forms.For example, in some embodiments the cover 14 can be a secondary framewith a generally skeletal form. In other embodiments, the cover 14 cansubstantially cover the base but leave certain windows open. Thus,downward facing recesses on the cover 14 that receive the retractedwheels 22 need not be fully enclosed in all embodiments. Further, insome of these embodiments the cover 14 can have a multi-part form,including structural portion and an aesthetic portion to conceal thestructural portion such as a shroud. In other embodiments, the cover 14can be integrated into the frame 18.

As depicted in FIGS. 2A-3C and discussed above, the base assembly 10includes a frame 18. The frame 18 can include one or more wheelassemblies 20 and is depicted as having four. As depicted, the wheelassemblies are arranged in a rectangular orientation (although otherorientations and numbers of wheels are possible). Further, the frame 18has two side housings 30 connected both by a cross-beam 38 and anactuating shaft 54, and the wheel assemblies 20 mount at generallyopposite ends of the side housings 30 in hollow wheel receiving portions33. Each wheel assembly 20 can include a wheel 22 mounted to a wheelmount 26. The wheel mount 26 is best depicted in FIGS. 2B and 3C,extending out of the hollow wheel receiving portion 33 extendingdownward from the side housing 30.

In some embodiments the wheel mount 26 can include an internal spring orshock 24 (depicted in FIG. 3C) that can reduce stresses on the frame 18,the base assembly 10, and the umbrella system 1, due to shocks such asbumps in a surface the wheels 22 roll over. Additionally, a biasingelement such as a spring 24 can help push the wheels 22 into thedeployed position. As shown, the spring 24 can be positioned generallybetween the wheel assembly 20 and the side housing 30. Thus, the spring24 can push the wheel assembly 20 away from the side housing 30, andtoward the deployed position. The force with which the spring 24 biasesthe wheels 22 into the deployed position can be configured to begenerally less than the force necessary to deploy the wheels. In someembodiments, the deployment of the wheels 22 coincides with a lifting ofthe umbrella assembly 1 off the cover 14. Thus, even with the spring 24,the wheels 22 can still remain in a retracted position and the cover 14can substantially support the load, despite the countervailing bias fromthe spring. This countervailing bias provided by the spring can alsoreduce the force on the actuating member 58 necessary to deploy thewheels 22, as it can press the wheels 22 toward such a position.

As further depicted, the wheel assembly 20 can mount to one or more pins42 within a vertical slot 36 a in the wheel receiving portion 33, and toa wheel connector 40 with a matching connector on the opposite side viathe pin. As best depicted in FIG. 3C, the pin 42 in the vertical slot 36a could potentially interfere with the spring 24. Accordingly, in someembodiments the pin 42 in the vertical slot 36 a can be a pair ofshortened fasteners that do not protrude through the entirety of thewheel receiving portion 33 and the two wheel connectors 40 on eitherside thereof. For example, there can be two pins 42 (one on each side ofthe wheel receiving portion) that each pass through a wheel connector40, one side of the vertical slot 36 a, and an adjacent side of thewheel mount 26. In some embodiments the pin 42 can thread into the wheelmount 26, thus securing the wheel mount to the wheel connector 40 by ascrew-connection.

The connectors 40 can also mount within a horizontal slot 36 b via oneor more pins 42. Additionally, this pin 42 can extend through a side ofthe wheel connectors 40 opposite the other pin 42. The pin 42 canpotentially be held by a screw and bolt connection (although otherarrangements are contemplated). Each of the pins 42 can allow relativerotation and translation between the wheel connectors 40 and thevertical and horizontal slots 36 a, 36 b, as the pins 42 translatethrough the slots. Thus, the wheel assembly 20 can translate vertically,through the wheel receiving portion 33, as the associated pin 42translates through the vertical slot 36 a. This can occur in response toa horizontal motion of the pin 42 in the horizontal slot 36 b, via theconnector 40 spanning the pins. Accordingly, the wheel assembly 20 canbe moved between at least two positions: one of which being deployed andextending farther out of the wheel receiving portion 33 to support theumbrella system 1; and the other being more retracted into the wheelreceiving portion and allowing the cover 14 to support the umbrellasystem.

As described above, all four wheel assemblies 20 in the depictedembodiment have motion controlled by a mechanism. However, otherembodiments are contemplated, in combination with the other featuresdescribed herein. For example, as depicted, the two wheels closer to thefoot pedal 58 can have an additional set of bearings 28 allowing thesewheels to swivel independently, improving the steerability of theumbrella system 1. In other embodiments, the slots 36 a,b can beoriented in other directions and the wheel connectors 40 can havedifferent shapes or forms. Further, in some embodiments the wheelassemblies 20 can move via other mechanisms such as a gear-assembly thattranslates horizontal motion into vertical motion (such as a worm gearinteracting with a standard gear) or a slider pressing against a slantedsurface.

The pin 42 mounted in the horizontal slot 36 b can also mount to aroller 44. The roller 44 can be positioned within an extended hollowshaft 32 of the side housing 30. In some embodiments, the roller 44 caninclude two wheels surrounding a transmission member in the form of atransmission member 46 that is also mounted on the pin 42, as bestdepicted in FIGS. 3A-3C. In the illustrated embodiments, thetransmission member 46 is a rod. As will be described further below, thetransmission member 46 can transmit an actuating force from an actuatingmember such as the lever 58 to the wheel assemblies 20 that are on theopposite side of the base assembly 10. Thus, the wheels 22 on both endsof the base assembly 10 can be moved between deployed and retractedpositions.

Additionally, the transmission member 46 can include a control mountingsection 48 in an intermediate section of the transmission member. Aswill be further discussed below, this control mounting section 48 of thetransmission member 46 can be generally adjacent a corresponding controlmounting section 39 of the side housing 30, and the control mountingsections can receive associated components that can control the movementof the wheel assemblies 20.

As depicted, the opposite ends of the transmission member 46 can mountto the pins 42. The pins 42 can associate with wheel connectors 40, andin turn with wheel assemblies 20, on each side of the transmissionmember 46. The transmission member 46 can mount to or form a part of alinkage. In the depicted embodiment the linkage can include a firstconnector 50 at the end of the transmission member 46 closer to theactuating member 58. The transmission member 46 mounts to the firstconnector via a pin 42 in this embodiment. The pin 42 also connects to awheel connector 40, as discussed above. The first connector 50 can thusbe pivotally mounted to the transmission member 46, and can in turn bepivotally mounted to a second connector 52. The second connector 52 canthen be pivotally mounted to the side housing 30 at a rotationalmounting portion 34 depicted as being at an end of the side housing 30.Thus, rotation of the second connector 52 relative to the side housing30 can result in a translation of the transmission member 46 relative tothe side housing.

Further, an intermediate portion of the second connector 52 can receivean actuating shaft 54. As depicted, the actuating shaft 54 can have ahexagonal shape that resists rotation relative to a hexagonal hole inthe second connector 52 that receives the shaft. Other shapes,combinations of shapes (e.g., tight-fitting, non-circular shapes), andmechanisms (e.g. locking pin or clamp) are also possible for the shaftand corresponding hole. By these combinations of connections, a rotationof the actuating shaft 54 can cause a rotation of the second connector52 about the side housing 30, which can cause a translation of thetransmission member 46 as described above. Translation of thetransmission member 46 can cause the wheel assemblies 20 farther fromthe actuating member 58 to move between deployed and retractedpositions. Notably, the wheel assemblies 20 disposed closer to theactuating member 58 can have a more direct connection to the actuatingmember 58 (e.g., through the first and second connectors 50, 52). Thus,these closer wheel assemblies 20 can move between deployed and retractedpositions in the depicted embodiment, without the assistance of thetransmission member 46.

Thus, the rotation of the actuating shaft 54 can cause the motion of allwheel assemblies 20 between deployed and retracted positions in certainembodiments. However, in other embodiments different mechanisms can beused. For example, in some embodiments it may be desirable to onlydeploy/retract certain wheels, such as the wheels closer to or fartherfrom the actuating member 58. In other embodiments, the same wheels canbe moved by other mechanisms, such as a cam shaft on the actuating shaft54 pushing or pulling a transmission member 46. Even further, in someembodiments the motion can be actuated by a mechanism other than arotating shaft.

In the depicted embodiment, the rotation of the actuating shaft 54 canbe initiated via a rotation piece 56 also rotationally fixed with theactuating shaft with a hexagonal hole. The rotation piece 56 can includea slot that receives an actuating member 58 depicted as a lever with afoot pedal. Thus, when a user applies a downward pressure to the footpedal, the actuating member 58 can rotate and cause a correspondingrotation of the rotation piece 56 and the actuating shaft 54. Thisapplication of pressure to the actuating member 58 can thus cause amovement of the wheel assemblies 20 between deployed and retractedpositions. In other embodiments, this actuation can be supplied by othermechanisms such as a rotatable hand crank, translating foot pedal, orthe like. In some embodiments, a foot pedal may be preferable as thefoot can generally provide a stronger force, especially when pressingdownward.

In further embodiments, it may be desirable to provide additionalcontrols on the motion of the wheel assemblies 20. For example, when thewheels 22 are deployed and they hold the weight of the umbrella assembly1, the weight could be sufficient to push the wheel assemblies 20 backinto a retracted position. In some embodiments friction may besufficient to prevent this movement absent additional forces (such aspressure on the actuation member 58). Such friction can arise in thedepicted embodiment between the wheel assemblies 20 and the wheelreceiving portions 33, between the rollers 44 and the extended hollowshaft 32, and between the pins 42 and their various correspondingsurfaces. However, in other embodiments such friction might not besufficient. Further, greater control over the motion of the wheelassemblies 20 may be desired for other reasons, such as to put the baseassembly 10 into a safety lock to more robustly prevent motion.

Thus, a control assembly 60 can also be provided, as depicted in detailin FIGS. 3C-6. As discussed above, the side housing 30 and thetransmission member 46 can both include control mounting sections 39,48, to which control features can be mounted. The side housing's controlmounting section 39 can include an extended slot on a lower portion ofthe side housing, and a plurality of mounting holes to receive a platemount 62. The transmission member's control mounting section 48 caninclude a pin slot 49 facing downward, and a similar plurality ofmounting holes to receive a pin housing 66.

The plate mount 62 can receive a control element such as the depictedcontrol plate 70, and the pin housing 66 can receive a pin 68. With thehousing 66 and mount 62, relative motion can be provided between the pin68 and the plate 70 as the transmission member 46 moves through theextended hollow shaft 32 of the side housing 30. This relative motioncan overlap with surfaces of the control element 70 that define one ormore stable holding positions in which the pin 68 can stop. Theseposition can, for example, correspond to positions of the transmissionmember 46 associated with deployed and/or retracted positions of thewheel assemblies 20. In some embodiments, a controlled relative movementbetween the pin 68 and the plate 70 is provided by one or more contoursdefined on the plate 70. In some cases, at least one protrusion isprovided to cause a change in the direction of the relative movement ofthe plate 70 and/or the pin 68.

As best depicted in FIG. 6, the pin 68 can have a circular T-shape,although other shapes are possible. A circular T-shape can include, forexample, an elongate cylinder extending away from a shorter and widercylinder. The pin 68 can reside within a slot 49 in the transmissionmember 46 shaped to accommodate a wider portion 68 a of the pin.Further, the pin 68 can be movably mounted within the pin housing 66,the pin housing 66 mounted around the slot 49. Thus, the pin 68 can beretained in the slot 49 by the pin housing 66, which is depicted as aU-shaped bracket shaped to mount on the transmission member 46 and caninclude generally semi-circular cut-outs to accommodate the widerportion 68 a of the pin (see FIGS. 4A-4F, 6). However, at the base ofthe pin housing 66 the housing can include a bore sized to onlyaccommodate a narrower portion 68 b of the pin 68, as depicted in FIG.6. Accordingly, the pin housing 66 can retain the pin 68 and hinder thepin's escape from the pin housing 66 and the slot 49 in the transmissionmember 30. The pin housing 66 can then be securely fixed to thetransmission member 46 by pin or screw joints that can pass through thepin housing 66 and optionally also the transmission member.

Thus, the pin housing 66 and slot 49 can define a central bore thatallows travel of the wider portion 68 a of the pin 68 within the pinhousing. This can allow the pin 68 to move up and down within the pinhousing 66 and the slot 49, such that the length of the narrow portionof the pin 68 extending beyond the housing can increase and decrease asthe pin moves. This movement can bring the pin 68 to extended andretracted positions. Simultaneously, the pin 68 can interact with thecontrol plate 70, as further described below. In some embodiments, thepin 68 can also be biased to an extended position by gravity, by aspring mounted within the housing 66, magnetic forces between the pinand other features, or other mechanisms.

Similar to the pin housing 66, the plate mount 62 can have a U-shape andbe securely fixed to the side housing 30 much like the pin housing 66mounts to the transmission member 46. Also like the pin housing 66, theplate mount 62 can have a bore through its base that can receive a pin.The depicted plate mount 62 also includes a lower slot 63 on a side ofthe base of the U-shape features, as best shown in FIGS. 3C, 4A. Withinthe slot 63, the plate mount 62 can receive a control plate 70 in thelower slot 63, mounted on a pin passing through the bore in the platemount 62. Thus, the control plate 70 can be rotatably mounted at a pivot89 to the plate mount 62, and accordingly to the side housing 30.

The control element 70, depicted as a control plate can be substantiallyplanar or semi-planar and have a contoured upper surface adjacent thepin 68 and a spring mounting portion 88 on an opposite side of thecontrol plate's pivot 89 from the contoured surface. A spring 64 canattach to the control plate 70 at the spring mounting portion 88 andextend to a spring mounting portion 37 on the side housing 30. The sidehousing's spring mounting portion 37 can be generally adjacent the wheelreceiving portion 33 nearer the actuating member 58, but otherorientations and positions are contemplated. The spring mounting portion88 of the control plate 70, along with the spring 64, can bias thecontrol plate to rotate to a position generally aligned relative to,e.g., the pin 68. In other embodiments this bias can be achieved bydifferent mechanisms, such as a torsional spring, a bendable plate, aleaf spring, or the like. As will be further discussed below, thecontrol plate 70 can be rotated out of its aligned position by the pin68, but can then return to this position under the force of the spring64.

The contoured surface 70 a is best depicted in FIGS. 5, 5A. On one sideof a contoured end 70 b of the control plate 70, the control plate canhave an angled portion 72. The angled portion 72 can form a gradualincrease in height of the upper surface of the control plate 70, or agradual thickening of the control plate. The angled portion 72 cantransition into a first broad portion 74. In the depicted embodiment thetransition can be at a corner, but in other embodiments there can be asmooth transition between the angled portion 72 and the first broadportion 74.

As depicted, the first broad portion 74 can be generally flat, althoughthis may vary in other embodiments. Also, the broad portion 74 need notnecessarily be wider than the angled portion 72, but rather can have anarrower region near the angled portion 72 and a wider region spacedfarther away from the angled portion 72. The first broad portion 74 caninclude a plurality of guide features, which can be configured asprotrusions that extend away from the generally flat area of the firstbroad portion 74. The guide features are shown in the figures as a guidepiece 76 and a hook 78 protruding up from the broad portion. The guidepiece 76, as depicted, can be generally triangular and centered alongthe control plate 70, spaced from the angled portion 72 by the firstbroad portion 74. The hook 78 can have a generally curved shape and belocated between the guide piece 76 and the angled portion 72. The hook78 can have a concave portion facing into the control plate 70 andtoward the pivot 89, to form a holding portion 80. A convex portion ofthe hook 78 can face toward the contoured end 70 b of the control plate.As further depicted, the convex portion of the hook 78 can include aslanted wall 79 along the angled portion 72. The slanted wall 79 canextend transverse to a center of the control plate 70. In someembodiments, a guide feature is provided in place of the hook 78 thathas an angled surface on one side and a notch on the opposite side. Theangled surface can extend the entire width of the guide feature, e.g.,transversely across the plate 70. The angled surface can form oneportion of a convex surface. In some embodiments, the notch comprisestwo surfaces angled toward each other, e.g., a concave surface.

Between the guide piece 76 and the hook 78, the first broad portion 74can meet a first offset portion depicted as a first ledge 82. The firstledge 82 can be between the guide piece 76 and the hook 78, and separatethe first broad portion 74 from a second broad portion 84. In someembodiments the first ledge 82 can extend at an angle relative to thelongitudinal axis of the guide plate 70 (see FIG. 5). The ledge 82 canbe disposed between the guide piece 76 and the hook 78 to separate thebroad portions 74, 84. The second broad portion 84 can also be generallyflat, although that can also vary in other embodiments. The second broadportion 84 can extend to a second offset portion depicted as a secondledge 86 at the end of the contoured surface 70 a of the control plate70. Thus, as depicted, the edge 70 b of the contoured surface 70 a ofthe control plate 70, opposite from the spring mounting portion 88, canbe include two portions: the angled portion 72 and the second ledge 86.

The pin 68 can move along the contoured upper surface 70 a of thecontrol plate 70 to control the motion of the wheel assemblies 20 uponactuation of the actuating member 58. This control of the motion alongthe control plate 70 is best depicted in FIGS. 4A-4F and 5A. As depictedin FIG. 4A, the pin 68 can initially be fully extended away from the pinhousing 66 and generally separated from the control plate 70. The pin 68can be stable in this position, and thus form a first stable position.The transmission member 46 can be configured to have a positioncorresponding to the first stable position of the pin 68, wherein thetransmission member is disposed generally away from the actuating member58, with the wheel assemblies 20 disposed in a retracted position asdiscussed above.

Then, upon actuation of the actuating member 58, such as a pump of thefoot pedal, the transmission member 46 can translate toward theactuating member 58. This translation can bring the wheel assemblies 20into a deployed position, as discussed above. Additionally, the motioncan move the pin 68 toward the control plate 70, as best depicted inFIGS. 4B, 4C. The pin 68 can contact the slanted wall 79, which canguide the pin 68 along the angled portion 72 of the plate 70. In oneembodiment the slanted wall 79 extends generally transversely across acentral portion of the control plate 70, and the control plate 70 isbiased toward a centered position. In this embodiment, initial contactbetween the pin 68 and the plate at the slanted wall is encouraged. Inother embodiments, the slanted wall 79 can extend transversely on theplate 70 between two ends both of which are offset laterally of alongitudinal axis of the plate 70. For example, the slanted wall 79 canbe configured such that a projection of the ends of the wall onto aplane perpendicular to the longitudinal axis of the plate 70 is lessthan half the width of the plate 70. These arrangements enable relativesliding movement of the pin 68 relative to the plate 70 without causingthe pin 68 to travel beyond the lateral edge of the plate. The movementto the angled portion 72 can be further encouraged by the second ledge86, which can generally hinder movement of the pin 68 onto the secondbroad portion 84.

As the pin 68 moves up the angled portion 72, the pin can generally moveinto a retracted position within the pin housing 66. Further, the pin 68can push against the slanted wall 79, causing the control plate 70 torotate, accommodating the pin's motion toward the control plate, as bestdepicted in FIG. 4B. For matters of convenience, at some portions hereinthe pin may be described as moving in a lateral or transverse directionalong the control plate, which includes movement that is perpendicularto the primary axis of the transmission member 46. However, in thedepicted embodiment it will be understood that this is a relativemovement, partially caused by the rotation of the control plate 70relative to the side housing 30, the pin 68, and the remainder of theumbrella system 1. Nevertheless, in other embodiments the pin 68 can beconfigured to move in such lateral or transverse directions, such aswithin a lateral or transverse slot in the pin housing 66 as a contouredsurface 70 a remains in a static position. Similarly, in someembodiments the pin 68 can remain in a static lateral and transverseposition as the contoured surface 70 a travels relative to the pin.

After the pin 68 has moved up the angled portion 72, it can be held inits retracted position within the pin housing 66 by the first broadportion 74. The pin 68 can eventually move along the first broad portion74, past the slanted wall 79 of the hook 78. Subsequently, the controlplate 70 can pivot back toward a centered position, as the pin 68 nolonger contacts the hook 78 to push the plate, as best depicted in FIG.4C. However, the pin 68 thereafter can contact the guide piece 76. Inthe depicted embodiment, the guide piece 76 contacting the pin 68 canhold the control plate 70 slightly off-center, e.g. rotated inwardlytoward a central area of the frame 18. At this point, the actuatingmember 58 can be released, allowing the transmission member 46 totranslate back and away from the actuating member. This can similarlycause the pin 68 to move back, away from the control plate 70, andtoward the angled portion 72. However, the pin 68 can be guided by theguide piece 76 into the concave holding portion 80 of the hook 78, asbest depicted in FIG. 4D.

The hook 78 can define a holding portion 80, where the pin 68 can begenerally held to hinder further relative translation between the pin 68and the control plate 70. Similarly, this can generally hinder furthermovement of the transmission member 46 and the wheel assemblies 20relative to the rest of the umbrella system 1. Thus, in someembodiments, the wheel assemblies can then be locked in a deployedposition. As discussed above, in this position the force of the load onthe base assembly 10 is directed to urge the wheel assemblies 20 towarda retracted position, and correspondingly to urge the pin 68 away fromthe control plate 70. However, this force and urged motion can besubstantially opposed and prevented by the hook 78.

The pin 68 can be brought out of engagement with the hook 78 and theholding portion 80 upon a second actuation of the actuating member 58,as best depicted in FIG. 4E. Upon this second actuation, the pin 68 canbe moved toward the pivot 89. The pin 68 can then encounter anothersurface of the guide piece 76, which can bias the pin toward the secondbroad portion 84 and the first offset portion 82 (or alternatively,rotate the control plate 70 as such). The pin 68 can then pass over thefirst offset portion 82, allowing the pin 68 to extend further out ofthe pin housing 66.

Then, when the actuating member 58 is released the pin 62 can move offthe second broad portion 84 (and the control plate 70) and over thesecond offset portion 86, as best depicted in FIG. 4E. This path can beguided by the first offset portion 82. The first offset portion 82 canbe substantially steep such that the pin 68 can not easily move backonto the first broad portion 74, which is higher than the second broadportion 84. Additionally, the first offset portion 82 can be angled,guiding the pin 68 toward the second offset portion 86. This angledportion of the first offset portion 82 can cause a rotation of thecontrol plate 70 that is similar to that caused by interactions betweenthe pin 68 and the slanted wall 79 discussed above. In some embodimentsthis rotation can be in the opposite direction, for example toaccommodate the pin 68 on the opposite side of the control plate 70.

The pin 68 can then pass over the second offset portion 86 and return toits original extended position as depicted in FIG. 4F. Similarly, thecontrol plate 70, via the force of the spring 64, can return to itsoriginal rotational position. The second offset portion 86 can besubstantially steep, such that the pin 68 cannot easily move back ontothe second broad portion 84. Thus, with two actuations of the actuatingmember 58, the pin 68 can make a closed loop along the surface of thecontrol plate 70, bringing the pin 68 back to the position depicted inFIG. 4A. In one embodiment the motion of the pin 68 is configured suchthat the pin can also be guided through a non-intersecting loop.

In the motion of the pin 68 a plurality (e.g., two) stable positions canbe defined. First, depicted in FIG. 4A, the pin 68 can be fully extendedand generally off the control plate 70. Then, upon a first actuation orpump of the actuating member 58, the pin 68 can move into the holdingportion 80, as depicted in FIG. 4D. Then, upon a second actuation orpump of the actuating member 58, the pin 68 can return to the positionof FIG. 4A. Between the two positions the pin 68 traverses a guided pathon the control plate 70 as the wheel assemblies 20 move betweenretracted and deployed positions. In one embodiment the deployedposition corresponds with the holding portion 80 and the retractedposition corresponds with the pin positioned away from the control plate70.

Other embodiments are possible. For example, in some embodiments theretracted and deployed positions can be associated with other relativepositions between the pin 68 and the control plate 70, such as theretracted position being associated with the holding portion 80 and thedeployed position being associated with the pin 68 away from the controlplate 70. Additionally, in some embodiments the control plate 70 and thepin 68 can be arranged and formed to provide more than two stablepositions, such as where the control plate 70 defines more than oneholding portion 80. Providing ever more stable positions can allow agreater variety of positions for the wheel assemblies 20, or otherelements. For example, in some embodiments the pin 68 and the controlplate 70 can define a mid-deployed position where some but not all ofthe wheel assemblies 20 fully extend beyond the cover 14. Further, insome embodiments all of the stable positions can be defined with the pin68 contacting the control plate 70.

Various associations between the positions of the pin 68 and the controlplate 70 with the wheel assemblies 20 (or other elements) can be furthersupported by other features. For example, in some embodiments a biasingmember can be added that biases the control assembly 60 toward aparticular position. In one embodiment, a spring can be mounted betweenthe transmission member 46 and the side housing 30, pulling thetransmission member toward a position associated with the wheelassemblies 20 being deployed.

Further, in some embodiments the control assembly 60 can be used inother contexts. For example, in some embodiments the control assembly 60can control a reversible jack, a braking system, a locking mechanism orthe like. In such embodiments, the control assembly 60, includingelements such as the control plate 70 and the pin 68, can be separatedfrom the side housing 30 and other elements of the umbrella assembly 1.The control assembly 60 can then be integrated into an alternativeassembly with which it will be used.

The umbrella system 1 can be formed from a variety of materials. Forexample, in some embodiments a majority of the base assembly 10 can bemetal, such as the side housing 30. However, the wheels 22 and pins 20can be formed from other materials, such as a hardened plastic. The useof other materials is also contemplated as part of any of theembodiments described above.

Although the foregoing description of the preferred embodiment of thepresent invention has shown, described, and pointed out the fundamentaland novel features of the invention, it will be understood that variousomissions, substitutions, and changes in the form of the detail of theapparatus as illustrated, as well as the uses thereof, may be made bythose skilled in the art without departing from the spirit of thepresent invention.

1. A base assembly comprising: a load-bearing base comprising one ormore downward-facing recesses; one or more wheels rotatably mountedwithin the load-bearing base and movable between a first wheel positionwithin the one or more downward-facing recesses and a second wheelposition extending out of the one or more downward-facing recesses, anactuating member movably coupled to the base; a transmission rod coupledto the actuating member such that actuation of the actuating membercauses the transmission rod to translate relative to the load-bearingbase; a pin mounted to the transmission rod; a control plate rotatablymounted to the load-bearing base, the control plate comprising acountoured surface substantially defining a pin path wherein the pin canmove from a first stable position and enter into a second stableposition along the path upon a first actuation of the actuating member,and the pin can exit the second stable position and return to the firststable position along the path upon a second actuation of the actuatingmember; and wherein motion of the transmission rod causes the pin tomove between the first and second plate positions and the wheels tosimultaneously move between the first and second wheel positions.
 2. Thebase assembly of claim 1, further comprising a cover disposed on thebase opposite the at least one wheel, wherein the cover supports thebase when the wheel is in the first wheel position.
 3. The base assemblyof claim 1, wherein the path along which the pin moves from the firststable position to the second stable position is different from the pathalong which the pin moves from the second stable position to the firststable position.
 4. The base assembly of claim 3, wherein the pin ishindered from moving in a reverse direction along the path.
 5. The baseassembly of claim 4, wherein the path comprises one or more offsetportions.
 6. The base assembly of claim 1, wherein pin is held within ahousing mounted to the transmission rod, and the pin can move relativeto the transmission rod and the housing between extended and unextendedpositions.
 7. The base assembly of claim 6, wherein the pin is in anextended position at the first stable position, and in an unextendedposition at the second stable position.
 8. The base assembly of claim 6,wherein the pin is biased toward an extended position.
 9. The baseassembly of claim 1, wherein the first stable position is substantiallyoff of or away from the plate and the second stable position is in aholding portion of the plate.
 10. The base assembly of claim 1, whereinthe pin is generally biased toward the first stable position.
 11. Thebase assembly of claim 1, wherein the actuating member is a foot pedal.12. The base assembly of claim 1, wherein the control plate is rotatablymounted to the base.
 13. The base assembly of claim 12, wherein thecontrol plate is rotationally biased toward a centered position.
 14. Abase assembly comprising: a load-bearing base; an actuating levermovably coupled to the base; a transmission member operatively coupledto the actuating lever such that a pumping of the actuating lever causesthe transmission member to move relative to the load-bearing base; a pinmounted to one of the transmission member and the load-bearing base tomove in at least one direction relative to the transmission member orload-bearing base; a control element mounted to the other of thetransmission member and load-bearing base to move in at least onedirection relative to the transmission member or load-bearing base,wherein the control element comprises a surface defining at least onestable holding position for the pin such that the pin can be received inthe stable holding position upon a first pump of the actuating lever andcan be separated from the stable holding position upon a second pump ofthe actuating lever; and a plurality of wheels rotatably mounted to theload-bearing base and movable between a first wheel position notsupporting the base and a second position where the wheels can supportthe base, wherein the movement of the wheels corresponds with themovement of the pin relative to the control element.
 15. The baseassembly of claim 14, further comprising a cover disposed on the baseopposite the wheels, wherein the cover supports the base when the wheelsare in the first wheel position.
 16. The base assembly of claim 14,wherein the surface of the control plate generally hinders the pin frommoving directly back-and-forth as it moves into and out of the holdingposition.
 17. The base assembly of claim 16, wherein the surface of thecontrol plate generally directs the pin into a looped path in and out ofthe holding position.
 18. A control mechanism comprising: a pin disposedon a housing; and a control element disposed on the housing such thatthe control element can at least move relative to the pin, wherein thecontrol element defines a surface comprising: an angled portion; aholding portion; and an offset portion, wherein, a first motion of thecontrol element relative to the pin causes the pin to traverse theangled portion, a second motion of the control element relative to thepin generally opposite the first motion causes the holding portion toreceive the pin, a third motion of the control element relative to thepin generally in the same direction as the first motion causes the pinto be separated from the holding portion and to traverse the offsetportion, and a fourth motion of the control element relative to the pingenerally in the same direction as the second motion causes the pin tobe separated from the offset portion.
 19. The control mechanism of claim18, wherein the control element is rotatably coupled to the housing. 20.The control mechanism of claim 19, wherein the control element is biasedtoward a centered position.
 21. The control mechanism of claim 19,wherein a rotation of the control element partially defines the motionof the plate relative to the pin.
 22. The control mechanism of claim 19,wherein the motion of the control element relative to the pin causes thepin to exert a force on the control plate causing a rotation of thecontrol plate.
 23. The control mechanism of claim 18, wherein the offsetportions generally allow relative movement of the pin in a firstdirection across the offset portion and hinder relative movement of thepin in an opposite direction across the offset portion.
 24. The controlmechanism of claim 18, wherein the fourth motion can bring the pin to aposition generally adjacent the angled portion.
 25. The controlmechanism of claim 18, wherein the holding portion comprises a hook. 26.A method of controlling a base assembly comprising: pumping an actuationmember to deploy one or more wheels to lift a base assembly on saidwheels; causing a pin to be received in a holding portion on asemi-planar contoured surface in response to the pumping; holding thewheels in a deployed position via the pin being held in the holdingportion; and pumping the actuation member to separate the pin from theholding portion and retract the wheels from the deployed position. 27.The method of claim 26, wherein the step of causing a pin to be receivedfurther comprises bringing the pin from an extended position to aretracted position.
 28. The method of claim 26, wherein the semi-planarcontoured surface rotates as the pin is received in the holding portion.29. The method of claim 26, wherein the steps cause the pin to move in asubstantially non-intersecting loop relative to the contoured surface.